Maziar has a point, there really isnt any need to waste your money on DDR3. If I were you, i'd be taking advantage of the really cheap DDR2 prices. Get a good set of Corsair or Team Xtreem ddr2-800.
It's better instead of putting too much money in the DDR3 memory to put it in a great motherboard with all functionnality. Like evag 680I rev A1 or some others